Railway car handbrake mechanism with square chain-winding drum

ABSTRACT

The force exerted by the chain of a handbrake-applying mechanism is increased by tensioning the chain over a square drum that is rotated by a hand wheel through a pinion and gear. The drum has an outer square configuration for receiving flatwise alternate links of the chain and an inner square configuration, tangent to the outer square configuration, for receiving the intermediate chain links at right angles to the axis of rotation of the drum. The intermediate chain links are held in nonkinking relation to the alternate chain links by radially extending ribs located where the configurations are tangentially related at the ends of the sides of the inner square configuration which are concave and conform to the ends of the juxtaposed intermediate links. The square configurations provide pockets in a malleable iron casting for receiving the links of a 1/2 -inch alloy steel chain which conforms to the specifications of the National Association of Chain Manufacturers. When the hand brake mechanism is of the two way type, one end of the chain is connected to the brake rigging and the other end is connected directly to the handbrake mechanism housing or to a part of the car frame. With a quick release hand brake mechanism, the other end of the chain is connected through shock-absorbing anchor means to the car frame.

United States Patent [72] Inventor William F. Koehler Chicago, Ill. [21 Appl. No. 874,639 [22] Filed Nov. 6,1969 [45] Patented Aug. 31, 1971 [73] Assignee Cleveland Hardware & Forging Company,

Inc. Cleveland, Ohio [54] RAILWAY CAR HANDBRAKE MECHANISM WITH SQUARE CHAIN-WINDING DRUM 5 Claims, 7 Drawing Figs.

[52] US Cl 74/505, 254/ 167 [51] Int. Cl 605g 1/08 [50] Field of Search 74/505, 506, 507,508, 509,510, 511,254/167, 168; 267/71; 192/15, 16

[56] References Cited UN TTED STATES PATENTS 334,999 1/1886 Waterbury 267/71 X 1,037,589 9/1912 Browning 267/71 1,487,531 3/1924 Brewster 74/505 X 2,274,175 2/1942 Whitcomb... 254/168 X 2,667,331 ll1954 Robins et a1. 254/168 2,781,671 2/1957 Devonshire 254/167 X Primary Examiner-Milton Kaufman Attorney-Robert R. Lockwood ABSTRACT: The force exerted by the chain of a handbrakeapplying mechanism is increased by tensioning the chain over a square drum that is rotated by a hand wheel through a pinion and gear. The drum has an outer square configuration for receiving flatwise alternate links of the chain and an inner square configuration, tangent to the outer square configuration, for receiving the intermediate chain links at right angles to the axis of rotation of the drum. The intermediate chain links are held in nonkinking relation to the alternate chain links by radially extending ribs located where the configurations are tangentially related at the ends of the sides of the inner square configuration which are concave and conform to the ends of the juxtaposed intermediate links. The square configurations provide pockets in a malleable iron casting for receiving the links of a 6-inch alloy steel chain which conforms to the specifications of the National Association of Chain Manufacturers. When the hand brake mechanism is of the two way type, one end of the chain is connected to the brake rigging and the other end is connected directly to the handbrake mechanism housing or to a part of the car frame. With a quick release hand brake mechanism, the other end of the chain is connected through shock-absorbing anchor means to the car frame.

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SHEET 2 OF 4 RAILWAY CAR IIANDBRAKE MECHANISM WITH SQUARE CHAIN-WINDING DRUM This invention is an improvement over the handbrake mechanisms disclosed in Bretz, U.S. Pat. Nos. Re. 25,001, issued .lune 20, l96l, and 3,040,597, issued June 26, 1962.

The handbrake mechanisms disclosed in the above patents have been widely used for manually applying the brakes of railway cars. With the advent of railway cars of 100 or more tons capacity, difiiculty has been encountered in applying the required breaking force to stop'and hold stationary such cars when fully loaded. In view of the widespread use of the prior hand brake mechanisms, it is desirable to employ the general overall configuration and dimensions of the patented devices insofar as the hand wheel and housing are concerned but modified to provide increased brake-applying force without requiring an increase in the force required to be exerte manually for setting the brakes.

Among the objects of this invention are: To reduce the distance from the axis of rotation of the drum about which the brake-applying chain is tensioned to the chain links to increase correspondingly the tension applied to the chain for a given rotation of the drum; to employ for this purpose a square drum with pockets for receiving alternate and intermediate chain links in nonkinking relation; to hole the intermediate links at right angles to the axis of rotation of the drum by limiting endwise movement of the intermediate links; to provide an arcuate abutment at each end of each intermediate link conforming to the juxtaposed end surface of the respective intermediate link and preventing endwise movement thereof; to connect one end of the chain to the brake rigging and the other end of an anchor independent of the drum over which the chain is trained and with which it has a driving connection; to anchor the other end of the chain directly to the handbrake mechanism housing or to the car frame when a two-way handbrake mechanism is used; and to anchor the other end of the chain to the car frame through shock-absorbing means when a quick release handbrake mechanism is used.

According to this invention essentially the same mechanism housing in employed that is used in the above referred to patented constructions. Also essentially the same centers are used for the hand wheel shaft and pinion and the main gear and chain drum operated thereby. Instead of winding the brakeapplyirig chain around the entire circumference of the drum, which limits the extent that slack in the chain can be taken up, the free end of the chain is anchored to the mechanism housing and is long enough to loop downwardly and then over a drum embodying this invention and downwardly on the other side for connection to the braking system. The drum of this invention is symmetrical and is either cast integrally with the main gear or is formed as a separate part and secured to the main gear. The drum has outer and inner square configurations provided pockets for receiving, respectively, alternate links and intermediate links of the brake applying chain which preferably is'a 86-inch alloy steel chain conforming to the specifications of the National Association of Chain manufacturers. The pockets are shaped to receive the alternate links flatwise and parallel to the axis of rotation of the drum and to receive the intermediate links flatwise and at right angles to this axis. This makes it possible to minimize the distance between the axis of rotation of the drum and the line along which the chain is tensioned for applying the brakes. In order to prevent linking of the links, the ends of the pockets for the intermediate links have arcuate abutments and radial sidewalls which prevent relative endwise movement of the intermediate links and maintain them in a plane at right angles to the axis of rotation of the drum. Regardless of the extent of tensioning or slackening of the chain, its links are held in nonkinking relation and thus the chain is always maintained in the same relative relation to the drum. When a two-way handbrake mechanism, such as that disclosed in U.S. Pat. No. Re. 25,001, is employed, the free end of the chain is anchored directly to the mechanism housing or to the car frame. The

free end of the chain is connected to the car frame through shock-absorbing anchor means when a quick release hand brake mechanism, such as that disclosed in U.S. Pat. No. 3,040,597 is used.

In the drawings:

FIG. 1 is a view, partly in front elevation and partly in section showing a two-way handbrake mechanism in which this invention is embodied.

FIG. 2 is a vertical section view taken generally along line 22 of FIG. 1.

FIG. 3 is a top plan view, at an enlarged scale, of the chain drum shown in FIGS. 1 and 2.

FIG. 4 is a sectional view taken generally along the line 4-4 of FIG. 3 and shows the relation between the chain links and the sides of the square chain drum.

FIG. 5 is a sectional view taken generally along line 5-5 of FIG. 4.

FIG. 6 is a view, at an enlarged scale and somewhat diagrammatic in character, to illustrate the details of construction of the chain drum.

FIG. 7 is a view, similar to FIG. 1, showing a quick release handbrake mechanism embodying this invention.

In FIGS. 1 and 2 the reference character 10 designates, generally, a handbrake mechanism that is intended for mounting on a railway car. The particular location on the car will depend upon the car construction. The mechanism 10 is of the two-way type shown in U.S. Pat. No. Re. 25,001 and includes a case, shown generally at 11, that is made up of a metallic cover 12 having an out turned flange 13 for overlying a back plate 14 to which it is secured. The mechanism 10 is mounted at a convenient location of the car body.

The handbrake mechanism 10 is intended for manual application of the brakes of the railway car. It is used principally for holding the car in a given position on a siding or to control the speed of and the stop the car, at a given point during switching, etc. For this purpose a chain, indicated generally at 15, is employed. Preferably the chain 15 is r-inch alloy steel welded chain conforming to the specifications of the National Association of Chain Manufacturers. The chain 15 comprises alternate links 16 and intermediate links 17. One end 18, as indicated in FIG. l, is arranged to be connected to the brake rigging of the railway car while the other or free end 19 is connected by a pin 20 to a chain anchor 21 that is suitably secured to the case lll. This is feasible since the brakes are applied and released gradually by the hand brake mechanism 10.

The chain 15 is trained over a square drum that is indicated, generally, at 22. The square drum 22 preferably is formed of malleable cast iron and it includes a radial flange 23 that is secured by rivets 24 to a main gear 25. Alternatively the square drum 22 and integral flange 23 can be cast integrally with the main gear 25. Both the square drum 22 and the main gear 25 are rotatably mounted on a shaft 26, FIG. 2, that extends between the cover 12 and the back plate 14.

For tensioning or slackening the chain 15 the main gear 25 meshes with a pinion 27 that is freely rotatably mounted on a hand wheel shaft 28 which is journaled between the cover 12 and the back plate 14. A section 29 on the handwheel shaft 28 is arranged to nonrotatably receive a handwheel 30.

Interconnecting the pinion 27 and the handwheel shaft 28 is a drive mechanism that is indicated, generally, at 31. The drive mechanism can be constructed as disclosed in the aboveidentified U.S. Pat. No. Re. 25,0011. Alternatively it can be constructed as disclosed in the above identified U.S. Pat. 3,040,597. Ratchet teeth 32 are provided on the drive mechanism 31 for cooperation with a pawl 33 to hold the chain 15 under tension when the brakes are set.

FIGS. 3-6 show, in more detail, the construction of the square drum 22 over which the alternate links 16 and intermediate links 17 of the chain 15 are trained. Referring particularly to FIG. 6 it will be noted that the square drum 22 comprises an outer square configuration 34 which may have a length at each side of 2.75 inches. Inside the outer square configuration 34 there is an inner square configuration 35 which has a length on each side of about 1.96 inches. These configurations are tangentially related at 36 or midway the length of each side of the outer square configuration 34. As illustrated, the alternate links 16 are arranged to lie flatwise along the sides of the outer square configuration 34 while the intermediate links 17 are positioned along the sides of the inner square configuration 35 and at right angles to the axis of rotation of the square drum 22 which is indicated at 22'. As shown more clearly in FIG. 5, the intermediate links 17 are positioned between radially extending sidewalls 37 which are coextensive with the intermediate portions of the sides of the inner square configuration 35.

As the square drum 22 is rotated, it is essential that the links of the chain 15 be maintained in the relationships shown in the drawings in order that a nonkinking relationship is maintained. It is for this purpose that radially extending ribs 38 having flat outer end surfaces'39 are formed at the ends of the sides of the inner square configuration 35 with concave end portions 40 of the sides of the inner square configuration 35 extending along the sides of the ribs 38 and conforming to the configuration of the juxtaposed end portions of the intermediate links 17.

By providing the radially extending sidewalls 37 the radially extending ribs having the concave portions 40 along the sides thereof, a driving connection is provided between the chain 15 and the drum 22. The intermediate links 17 of the chain 15 are prevented from having any relative endwise movement with respect to the square drum 22 and also they are held in a plane that extends at right angles to the axis 22' of the square drum 22.

For applying the brakes by tensioning the chain 15, the hand wheel 30 is rotated in a clockwise direction indicated by arrow 41, FIG. 1, to rotate the square drum 22 in the opposite direction. As the square drum 22 is rotated, the alternate links 16 and the intermediate links 17 are moved together with the respective sides of the outer square configuration 34 and inner square configuration 35. The slack that is taken up by tensioning the chain 15 is accommodated by the looping downwardly of that portion of the chain 15 which is connected by the pin 18 to the chain anchor 19. Using the construction described above, the distance between the axis 22' of rotation of the square drum 22 and the line along which the chain 15 is tensioned is reduced to a minimum thereby making it possible for the brakeman to apply a greater tension to the chain 15 than heretofore was possible using the constructions of the prior art, such as those disclosed in the patents above referred to.

It will be observed that two sets. of pockets are provided around the square drum 22. One set of pockets is individual to the alternate links 16 and is formed, in part, by the sides of the outer configuration 34 with the radially extending ribs 38 located centrally of the alternate links 16. The other set of pockets is formed by the sides of the inner square configuration 35 with respect to which the intermediate links 17 are juxtaposed and located between the radially extending sidewalls 37 and prevented from endwise movement by the concave end portions 40 of the sides of the inner square configuration 35 or of the sides of the ribs 38.

To release the brakes, the handwheel 30 is rotated in the direction indicated by arrow 42 when the drive mechanism 31 is employed.

Referring now to FIG. 7, the reference character designates, generally, a handbrake mechanism of the quick release type such as that disclosed in the above U.S. Pat. No. 3,040,597. It includes a case 11 and a cover 12 having an outstanding flange 14. There is provided a back plate 14'. The chain, previously described and shown generally at 15, is made up of alternate links 16 and intermediate links 17. One end 18 is connected, as illustrated, to the brake rigging while the other end 19 is arranged to be anchored in a manner to be described. The chain is arranged to be wound over a square drum 22 in the manner described hereinbefore. The square drum 22 includes the flange 23 that is secured by rivets 24 to the main gear 25 which is rotatably mounted on the shaft 26.

In the manner described hereinbefore provision in made for rotating the main gear 25 on rotation of the handwheel 30 for rotating the square drum 22 to apply the brakes by tensioning the chain 15.

As described in U.S. Pat. No. 3,040,597, the handbrake mechanism 11 is provided with a first trip lever 45 that is arranged to be operated remotely. A second trip lever 46 is located adjacent the handwheel 30 and is provided to permit quick release of the brakes in the same manner that the first trip lever 45 accomplishes this purpose. When the brakes are released quickly by operation of either the first trip lever 45 or the second trip lever 46, substantial force is applied to the other end- 19 of the chain 15 when the slack in it is run out which it is not feasible to resist employing the pin 20 and chain anchor 21 previously described for use with the two-way handbrake mechanism 10.

In order to absorb without damage shock-absorbing anchor means, indicated generally at 47, is connected to the other end 19 of the chain 15. The shock-absorbing anchor means 47 includes an angle bracket, indicated generally at48, which has one flange 49 that is arranged to be bolted to the car frame, for example, to an end sill or to another frame part. The angle bracket 48 also includes an outstanding flange 50 that is apertured for receiving therethrough a pull rod 5 1. At its lower end the pull rod 52 extends through a washer 52 and a nut 53 is threaded on this end underneath the washer 52. Between the outstanding flange 50 and the washer 52 there is positioned a coil compression spring 54 that is employed for absorbing the shock incident to quick release of the handbrake mechanism 10'. It will be noted that the last link 16 of the chain 15 is located between arms 55 of the bifurcated upper end 56 of the pull rod 51. A pin 57 extends through the arms 55 and the last link 16 to provide the required connection.

Preferably the coil compression spring 54 has an outside diameter of 3 inches and, in the unstressed condition, it is 10 inches long. It is of such material that it compresses l-Vz inches when subjected to a load of the order of 4,000 to 5,000 pounds. It will be understood that other spring characteristics can be employed depending upon the stress to which the other end 19 of the chain 15 is subjected when the brakes are fully released and the slack in the chain 15 runs out.

What is claimed as new is:

1. A railway car brake mechanism having a handwheel for rotating a gear wheel to apply the brakes comprising:

a chain,

a square drum rotatable with said gear wheel for receiving 1 alternate links of said chain flatwise on its sides and the intermediate links at right angles to the axis of rotation of said drum as said drum is rotated,

said square drum having an outer square configuration for receiving said alternate links and an inner tangentially related square configuration for receiving said intermediate links,

each side. of said square configuration having radially extending sidewalls to receive' therebetween said intermediate links, and

means for holding said intermediate links in nonkinking relation of said alternate links as said drum is rotated to tension said chain including radially extending ribs located where said square configurations are tangentially related.

2. The railway car brake mechanism according to claim 1 inner square configuration is about 1,96 inches.

4. A railwaycar brake mechanism having a hand wheel for rotating a gear wheel to apply the brakes comprising:

a chain,

means for holding said intermediate links in nonkinking relation to said alternate links as'said drum is rotated to tension said chain including:

a pocket individual to each of said alternate links, and another pocket individual to each of said intermediate links having at each end an arcuate abutment conforming to the juxtaposed end surface of the respective intermediate link 5. The railway car brake mechanism according to claim 4 wherein said chain is a x-inch alloy steel chain conforming to the specifications of the National Association of Chain Manufacturers, and said drum is a malleable iron casting. 

1. A railway car brake mechanism having a handwheel for rotating a gear wheel to apply the brakes comprising: a chain, a square drum rotatable with said gear wheel for receiving alternate links of said chain flatwise on its sides and the intermediate links at right angles to the axis of rotation of said drum as said drum is rotated, said square drum having an outer square configuration for receiving said alternate links and an inner tangentially related square configuration for receiving said intermediate links, each side of said square configuration having radially extending sidewalls to receive therebetween said intermediate links, and means for holding said intermediate links in nonkinking relation of said alternate links as said drum is rotated to tension said chain including radially extending ribs located where said square configurations are tangentially related.
 2. The railway car brake mechanism according to claim 1 wherein the ends of the sides of said inner square configuration are concave and conform to the juxtaposed intermediate links and the ends of said ribs are flat and parallel to the respective sides of said outer square configuration.
 3. The railway car brake mechanism according to claim 2 wherein the length of each side of said outer square configuration is about 2.75 inches and the length of each side of said inner square configuration is about 1.96 inches.
 4. A railway car brake mechanism having a hand wheel for rotating a gear wheel to apply the brakes comprising: a chain, a square drum rotatable with said gear wheel for receiving alternate links of said chain flatwise on its sides and the intermediate links at right angles to the axis of rotation of said drum as said drum is rotated, and means for holding said intermediate links in nonkinking relation to said alternate links as said drum is rotated to tension said chain including: a pocket individual to each of said alternate links, and another pocket individual to each of said intermediate links having at each end an arcuate abutment conforming to the juxtaposed end surface of the respective intermediate link.
 5. The railway car brake mechanism according to claim 4 wherein said chain is a 1/2 -inch alloy steel chain conforming to the specifications of the National Association of Chain Manufacturers, and said drum is a malleable iron casting. 